10 ms·

'Asymptotic burnout' of planet-scale civilizations may explain Fermi Paradox

74 points by bnjemian 4y ago

andrewclunn 4y ago
Lots of pretty words that translate to "reduce population and living standards or die." If true this is the hardest warning that people refuse to hear. If false it is a way to co-op guilt and fear to sell control. How I wish I knew which it was.
- MattPalmer1086 4y ago
  The two are not mutually exclusive. We all know endless growth with finite resources is impossible. We can innovate do things more efficiently or differently and find solutions to previous limits of course. The hypothesis in the paper is simply that eventually a civilisation will encounter circumstances in which the timescale to solve it is longer than the time they have to do it. Then they must either achieve a form of homeostasis (and no growth) or die off (or retreat and start again). The boundary for this doesn't have to be a planet. It could be a solar system, or maybe more than one.
- sgt101 4y ago
  Or: allow population to fall and material prosperity as it is. Note: material prosperity is not the same as living standards, as there is more to life than things. There is no reason at all to think that 1Bn humans can't live on earth at early 21st C standards more or less indefinitely. 11bn at twice that level.... that's harder to see.
- denton-scratch 4y ago
  I didn't read it that way. The authors propose "homeostasis" as the alternative to extinction. They give Bhutan as an example of a country that has opted for homeostasis rather than growth; Bhutan has reduced neither living standards nor population. It seems to be a sociology paper. I find the writings of sociologists impossibly dense and obscure.
- hellotomyrars 4y ago
  I would say they’re inversely related. The more people, the less there is to go around. Even if standard of living continue to go up and have, as a function of the population, the two aren’t intrinsically linked by themselves. However as limited resources become more strained over a larger population, the divide and quality of life, certainly in average, has to go down. It may not be 10 years, 20 years, or even 100 years away but at the moment we have limited quantities of many resources. At some point these lines are going to cross and it is going to lead to a reduction in quality of life. Whether or not that will be blunted by trends in developed nations toward negative population growth remains to be seen. Novel technology that lets our resources go farther or allows us to gain new sources via space (asteroid capture or mining on other planets, etc.) could also change the tipping point. The doom and gloom of Malthusian theory is so far unrealized but I think it is hard to argue that the theory is sound at its base. Whether or not we can keep the lines from crossing is the only thing that keeps it unrealized.
novalis78 4y ago
Yet another Malthusian paper. Why would a planet’s boundary be the civilization’s boundary? This could be an issue on a super-earth and an inability to leave the rock with chemical rockets but even then… or, as Dr Zubrin would say ‘most dangerous are the people who believe a limit in resources is the reason that we must fight each other’
- dreen 4y ago
  That's what I've been thinking about for a while as well. Why live down the gravity well if you don't have to? Some might still choose it, much like some modern people choose to live in the forest. And in space, there is plenty of space for everyone.
  - trgn 4y ago
    Space is an unfathomably unpleasant place to move to. Maybe advanced extra terrestrials understand that better than we do.
    - dreen 4y ago
      You mean unpleasant to our current biology and with our current ability to build space habitats. Give it a few hundred years and things may look different.
    - Nomentatus 4y ago
      I think they said that about Las Vegas, once upon a time (before the dam was built, and before air conditioning.)
  - somenameforme 4y ago
    Abstractly, a planet is just a really really big starship. With technological advances, we could even eventually theoretically move planets. So phrased in another way, why would one choose to live their entire life in a small starship instead of a big one?
    - 4y ago
whiddershins 4y ago
What if there is no real way to create an advanced civilization without fossil fuels, and the existence of them is more rare than we can estimate?
- Thev00d00 4y ago
  Something I didn't learn until recently is that coal was only formed because at the time Bacteria hadn't yet evolved the ability to break down that plant matter.
  - Nomentatus 4y ago
    The lignin hypothesis: https://arstechnica.com/science/2016/01/why-was-most-of-the-earths-coal-made-all-at-once/ https://arstechnica.com/science/2016/01/why-was-most-of-the-...
- hakfoo 4y ago
  On an energy basis, I'm going to doubt this claim. I know there's a common theory that having all the cheap energy of fossil fuels made modern civilization possible, but I suspect it was more of an accelerator than a requirement. If you have fire and biomass of some sort-- wood, animal dung, etc-- you can get to steam power without too many problems. That gets you to US Civil War tech levels or so. You can build a basic global national transportation network and start mechanizing agriculture on wood-fired, steam powered equipment. That would be able to provide the level of manufacturing to start bootstrapping electricity-- likely focusing on stationary turbines around hydropower and geothermal sources once biomass hits scaling limits. You might end up seeing an earlier focus on electric transportation systems because the energy density of coal and oil aren't available. You also get telegraphy and radio from that. A society with electricity would also be have the footholds to start the development of modern physics and get to the splitting of the atom, and at that point, energy is supposed to become too cheap to meter. The bigger issue I could see is the chemical opportunities hydrocarbon deposits provide. I could imagine a society without fossil fuels plateauing at a 1870s tech level because of limitations on material technology-- higher-quality lubricants and eventually plastics being obvious missing pieces. They might be able to build an electric car, but it's going to rely on things like fabric-wrapped wires and mica insulation, and have to be lubed with tallow. This would probably only be a transient state though, because without having to compete with poking for goo in the Middle East, many of the "renewable X to oil" pipelines are economically interesting, so eventually, they do get synthetic materials and fuels, although likely at a high price that causes them to be used conservatively from day 1. Once you get to "abundant cheap energy", this likely ceases to be a huge issue. I'd imagine that this world would end up looking a lot like ours by a hypothetical "2100 AD" tech level. They built on synthetic fuels and electricity because there was no alternative, and we'll have forcibly transitioned to them because we exhausted the fossil stopgap options.
deleted 4y ago
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Roark66 4y ago
I find the idea that unless our civilisation changes its priorities from "unbounded growth" to "homeostasis" then we necessarily will suffer the "asymptotic burnout" comparable to papers written in 19th century predicting New York will drown in horse manure in next 75 years unless the growth is artificially stunted. Although the authors mention the role of periodic innovation as a factor that resets the curve of the resource consumption they dismiss it by stating the frequency of said innovation has to increase with increased energy usage and interconnectedness resulting in a certainty at some point innovation will not be fast enough to delay running out of resources. For this argument to work we have to accept unquestionably that "unbounded growth" has to continue until either a civilisation runs out of resources and regressed or achieves "enlightenment" and shifts its priorities towards homeostasis. To this I say why are they so sure, that as through growth of economic activity we raise our collective standard of living people don't start valuing their happiness over economic output? In fact observations of highly developed societies seem to support that. In addition the birth rate of people declines in modern societies often below replacement numbers so that "unbounded growth" looks really unlikely.
- matthewdgreen 4y ago
  We replaced horse manure as a waste product with greenhouse gases, which produced a local improvement but will very likely put large portions of New York City under water in this century. So based on the evidence accumulated so far, we haven’t demonstrated that we can find our way out of the resource/pollution dilemma. Maybe we will in the future!
  - parkingrift 4y ago
    We already know how to find our way out. Stratospheric aerosol injection. We don’t need to invent anything new or spend significant sums of money. We will do it eventually, but only after green democrats finish their “perfect is the enemy of good” lifetime crusade.
    - AlexandrB 4y ago
      "Know" is doing a lot of work here. > Almost all work to date on stratospheric sulfate injection has been limited to modeling and laboratory work.[1] At best it seems like a good potential solution that need a lot more study. [1] https://en.m.wikipedia.org/wiki/Stratospheric_aerosol_injection https://en.m.wikipedia.org/wiki/Stratospheric_aerosol_inject...
omnicognate 4y ago
The Fermi "paradox" is such an annoying meme. We have no evidence that extraterrestrial life isn't absolutely everywhere. To think we do is to greatly misunderstand the scale of the galaxy.
- MattPalmer1086 4y ago
  Why do you find it annoying? Other than it isn't a paradox of course. It's not claiming that life doesn't exist, it just provides a framework to discuss the current absence of evidence for it. The "where are they" question. We have conducted a lot of surveys and found nothing. There was a recent survey of galaxies that looked for Kardashev level 3 civilisations (control over the energy output of a galaxy) and we see nothing. So it seems reasonable that they are no K3 civilisations out there in our light cone. Simple life might be common, but we can't currently look for that easily, although bio signatures of gases in atmospheres is increasingly possible. It's also possible that complex civilisations are out there, but we just haven't figured out what that would look like. It's an ongoing search. The one thing we do know is if it's out there, it's not obvious.
  - omnicognate 4y ago
    I find it annoying because it's discussed on HN ad nauseam in debates that are speculative fiction at best and riddled with logical fallacies at worst. Take, for example, the "Chain of Reasoning" section of the Wikipedia page page about the "paradox", which ends with following two steps: > Since many of the stars similar to the Sun are billions of years older, Earth should have already been visited by extraterrestrial civilizations, or at least their probes. > However, there is no convincing evidence that this has happened. The "should" in the first doesn't follow from what goes before at all, and the second is one of the most basic logical fallacies: absence of evidence is not evidence of absence. And take your own point about "K3 civilisations". Let's lay it out: 1. A "K3 civilisation" is one that controls the energy output of a galaxy. 2. Therefore it would be detectable with our instruments. 3. Therefore the fact that we haven't detected one means there isn't one. This is just bad reasoning. 2 doesn't follow from 1 and 3 doesn't follow from 2. The "therefore" in 2 ignores the word "control" in "control of the energy output of a galaxy". It makes an implicit assumption that any civilisation in control of such resources would necessarily do something with those resources that would result in an amount of radiation detectable to our instruments being emitted in our particular direction, whether that's some focused signal directly targeted at us or some massive omnidirectional blast. Maybe they would choose to randomly set off supernova-sized blasts for shits and giggles, but maybe, you know, they wouldn't. For 2 to follow from 1 you need to know that such a civilisation would necessarily produce detectable signals and you don't. Then, for 3 to follow from 2 you have to assume that every signal reaching our planet that is capable of being detected by our instruments is in fact detected. That is hilariously far from being true. Yes, we have some amazing instruments, including ones that can capture enough light from a nearby planet to do spectroscopy on its atmosphere. But those instruments are not simultaneously pointed in every direction all the time. The exact number isn't knowable but certainly 99 and several 9s percent of the signals reaching the Earth at any one time that we could detect and analyse we are in fact not. You talk of surveys but the idea of "surveying" our galaxy (let alone the universe) sufficiently thoroughly to rule out the presence even of the sort of advanced civilisation that produces vast uncontrolled blasts of undirected energy (and of course there's no reason to think an advanced civilisation necessarily would) with current technologies and funding is laughable. You can't bootstrap knowledge from nothing. The universe is staggeringly vast and we've barely started to look at it. The knowledge we have at this stage places essentially no limits on the sorts of alien life that could exist or on how widespread it is. If you want to speculate about what's out there, please do. I love science fiction! Just don't pretend it's science and please don't claim certainty when your arguments achieve nothing of the sort.
BirAdam 4y ago
I think the Fermi Paradox is more easily explained by three things. 1. It is possible that self-aware life with the ability to manipulate the environment is rare. Most people assume that self-aware life will build cities, but crows, cetaceans, octopuses, and elephants don’t do so despite having quite a bit of smarts. They lack hands. 2. It is possible that the speed of light is a very real boundary and that cannot be broken limiting the ability of life to spread itself within a life time. As anything that persists spends energy to do so, it may be that living things won’t willingly take the chance for themselves and posterity of living on a ship for many generations. 3. Nuclear war. Most intelligent life is predatory. If you want to manipulate your environment, you also have to focus. Most animals with eyes on the front of their heads that can focus well, are also predators. That predatory instinct creates violence, and that leads to war in pack-oriented social predators. With enough advancement, nuclear weaponry and war may be the rule not the exception.
- admax88qqq 4y ago
  > living on a ship for many generations. Thanks to time dilation, with 1g of acceleration you can go anywhere in the galaxy and back in 40 years.
  - elkos 4y ago
    provided faster than light travel is possible right? Cause the galaxy is pretty big isn't it?
    - 4gotunameagain 4y ago
      I think he means that your local time passed will be 40 years, while much longer for the rest of non accelerating people. And of course I have no idea if the maths check out :)
      - qayxc 4y ago
        > And of course I have no idea if the maths check out :) The galaxy is about 90,000 ly across so a time dilation of about 0.004 is required to get to the 40 yr figure. Doing the Lorentz transformation results in a required speed of 299,790 km/s or 99.999% the speed of light. Needless to say that this is indeed practically unachievable by any macroscopic space craft. Even if you were able to accelerate a ship to such speed, said ship wouldn't survive the journey as radiation from the blue-shifted light of stars in front of it as well as interstellar particles would destroy any known material.
stared 4y ago
My take (which does not involve maths, just analogy with other organisms) is that we are bacteria that eat all that's on a petri dish. Dying as a species is (IHMO) rather unlikely, except for external factors and a few contamination scenarios. Eating all resources, starving most population, and going back to a pre-industrial civilization. Except for a few living high-tech standards. But with devices, they can use but cannot replace.
bohadi 4y ago
The burnout-collapse trajectory is another kind of homeostasis, only one with very wide range of variation. Though that produces huge human suffering and lossy cultural transmission so it might be worth avoiding. But homeostatic awakening is continually underway, from 20th century discourse of technique and enframing to our modern drives for global sustainability. Would it not be wise to err on the side of caution, reaching for the stars at some slowest effective rate (Elons per millenium;) until we know more? Another concern is civilization may execute both futures parallelly via splitting: where some 'elite' Gosper glider-like sets off from home planet, and the Gosper glider gun remains to reset the cycle. If collapse assumed this is your K shaped recovery. The Fermi paradox does not overly worry me for some reason. Everything Is just so improbable really.
deleted 4y ago
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AbrahamParangi 4y ago
There is an assumption embedded in the Fermi paradox which is that life might originate within an environment already colonized by life. This is not the case in our experience on earth. As far as we know, all life is related which means that all life descends from a common ancestor. If intelligent life relatively rapidly (say within 1M years) gains the ability to travel at near the speed of light and consume interstellar resources, then new life would never know. There is no case where you could look up and see a galactic empire because if you could see it then it would have been expanding long enough to reach you, and you wouldn’t exist.
- LorenPechtel 4y ago
  Disagree. Life on Earth showed up about as soon as it could. That says the development of life isn't a likely limit. We see only one form of life because having a head start let it outcompete everything else. We appear to be alone. That says something (or some combination of things) in the process of developing into a starfaring civilization must have billions-to-one odds against it. It's not planets--we see tons of planets. Earth-like ones don't show up much--but our detection techniques aren't very good at seeing Earth-like planets so we can't conclude much from that. The rapid appearance of life on Earth says that's not a likely barrier. Looking at history we have two candidates: the development of multi-cellular life and the development of intelligence. Both took billions of years on Earth. Note that humanity just squeaked in under the wire, about 99% of time Earth would be capable of evolving intelligence is already past. The sun has been slowly warming, this has driven more CO2 into limestone, offsetting the warming. This buffer has almost pegged, once it pegs solar warming turns into planetary warming and Earth is no longer suitable for species with long life cycles. If we are lucky we are extreme outliers in how fast one or both of those steps happened and the barrier is behind us. (This shouldn't be discarded on improbability--observer effect. Only a planet where that happened could develop a species that could note the issue.) If not, the limit is in the future. Either we destroy ourselves or we somehow turn inward and ignore the stars. Unfortunately, probably says it's one of the latter. It is possible for there to be a galactic empire and yet we exist--quarantine hypothesis. There's a galactic empire that strictly avoids any star systems with worlds where life can arise. However, such a galactic empire should be detectable anyway. A star wrapped in a dyson swarm will show a spectrum unlike anything we can see in the sky. From this we can conclude there are no dyson swarms in any part of the universe we can resolve stars. Earth shines in the radio spectrum. An ET pointing a radio telescope at us isn't going to be able to decode much of anything (any more than we could listen to a million voices at once) but they can see the energy.
csense 4y ago
This article claims population growth increases on shorter and shorter timescales, leading to infinite population growth. If this is true, we should have had baby boom, bigger echo boom, giant boom. Instead, we had baby boom, smaller echo boom, and now Social Security's about to implode because the original boomers are retiring without being replaced. (Or maybe being replaced by immigrants, which led directly to Donald Trump being elected and the near-implosion of our political system.) This article might be the basis for an interesting and thought-provoking sci-fi story. But if it's supposed to be a serious scientific prediction of what actual aliens in our own universe are like, it's just embarrassing. If you make claims of supposedly near-universal trends in alien societies and say those claims are basically guaranteed by math and physics, then your claims certainly ought to at least be consistent with what we observe in our one known data point of an actual intelligent civilization (ourselves). And for the claim of technological population acceleration, actual observation suggests the effect runs in the opposite direction, at least here on Earth.

74 points by bnjemian 4y ago

Lots of pretty words that translate to "reduce population and living standards or die." If true this is the hardest warning that people refuse to hear. If false it is a way to co-op guilt and fear to sell control. How I wish I knew which it was.

MattPalmer1086 4y ago
The two are not mutually exclusive. We all know endless growth with finite resources is impossible. We can innovate do things more efficiently or differently and find solutions to previous limits of course. The hypothesis in the paper is simply that eventually a civilisation will encounter circumstances in which the timescale to solve it is longer than the time they have to do it. Then they must either achieve a form of homeostasis (and no growth) or die off (or retreat and start again). The boundary for this doesn't have to be a planet. It could be a solar system, or maybe more than one.
sgt101 4y ago
Or: allow population to fall and material prosperity as it is. Note: material prosperity is not the same as living standards, as there is more to life than things. There is no reason at all to think that 1Bn humans can't live on earth at early 21st C standards more or less indefinitely. 11bn at twice that level.... that's harder to see.
denton-scratch 4y ago
I didn't read it that way. The authors propose "homeostasis" as the alternative to extinction. They give Bhutan as an example of a country that has opted for homeostasis rather than growth; Bhutan has reduced neither living standards nor population. It seems to be a sociology paper. I find the writings of sociologists impossibly dense and obscure.
hellotomyrars 4y ago
I would say they’re inversely related. The more people, the less there is to go around. Even if standard of living continue to go up and have, as a function of the population, the two aren’t intrinsically linked by themselves. However as limited resources become more strained over a larger population, the divide and quality of life, certainly in average, has to go down. It may not be 10 years, 20 years, or even 100 years away but at the moment we have limited quantities of many resources. At some point these lines are going to cross and it is going to lead to a reduction in quality of life. Whether or not that will be blunted by trends in developed nations toward negative population growth remains to be seen. Novel technology that lets our resources go farther or allows us to gain new sources via space (asteroid capture or mining on other planets, etc.) could also change the tipping point. The doom and gloom of Malthusian theory is so far unrealized but I think it is hard to argue that the theory is sound at its base. Whether or not we can keep the lines from crossing is the only thing that keeps it unrealized.

novalis78 4y ago

Yet another Malthusian paper. Why would a planet’s boundary be the civilization’s boundary? This could be an issue on a super-earth and an inability to leave the rock with chemical rockets but even then… or, as Dr Zubrin would say ‘most dangerous are the people who believe a limit in resources is the reason that we must fight each other’

dreen 4y ago
That's what I've been thinking about for a while as well. Why live down the gravity well if you don't have to? Some might still choose it, much like some modern people choose to live in the forest. And in space, there is plenty of space for everyone.
- trgn 4y ago
  Space is an unfathomably unpleasant place to move to. Maybe advanced extra terrestrials understand that better than we do.
  - dreen 4y ago
    You mean unpleasant to our current biology and with our current ability to build space habitats. Give it a few hundred years and things may look different.
  - Nomentatus 4y ago
    I think they said that about Las Vegas, once upon a time (before the dam was built, and before air conditioning.)
- somenameforme 4y ago
  Abstractly, a planet is just a really really big starship. With technological advances, we could even eventually theoretically move planets. So phrased in another way, why would one choose to live their entire life in a small starship instead of a big one?
  - 4y ago

whiddershins 4y ago

What if there is no real way to create an advanced civilization without fossil fuels, and the existence of them is more rare than we can estimate?

Thev00d00 4y ago
Something I didn't learn until recently is that coal was only formed because at the time Bacteria hadn't yet evolved the ability to break down that plant matter.
- Nomentatus 4y ago
  The lignin hypothesis: https://arstechnica.com/science/2016/01/why-was-most-of-the-earths-coal-made-all-at-once/ https://arstechnica.com/science/2016/01/why-was-most-of-the-...
hakfoo 4y ago
On an energy basis, I'm going to doubt this claim. I know there's a common theory that having all the cheap energy of fossil fuels made modern civilization possible, but I suspect it was more of an accelerator than a requirement. If you have fire and biomass of some sort-- wood, animal dung, etc-- you can get to steam power without too many problems. That gets you to US Civil War tech levels or so. You can build a basic global national transportation network and start mechanizing agriculture on wood-fired, steam powered equipment. That would be able to provide the level of manufacturing to start bootstrapping electricity-- likely focusing on stationary turbines around hydropower and geothermal sources once biomass hits scaling limits. You might end up seeing an earlier focus on electric transportation systems because the energy density of coal and oil aren't available. You also get telegraphy and radio from that. A society with electricity would also be have the footholds to start the development of modern physics and get to the splitting of the atom, and at that point, energy is supposed to become too cheap to meter. The bigger issue I could see is the chemical opportunities hydrocarbon deposits provide. I could imagine a society without fossil fuels plateauing at a 1870s tech level because of limitations on material technology-- higher-quality lubricants and eventually plastics being obvious missing pieces. They might be able to build an electric car, but it's going to rely on things like fabric-wrapped wires and mica insulation, and have to be lubed with tallow. This would probably only be a transient state though, because without having to compete with poking for goo in the Middle East, many of the "renewable X to oil" pipelines are economically interesting, so eventually, they do get synthetic materials and fuels, although likely at a high price that causes them to be used conservatively from day 1. Once you get to "abundant cheap energy", this likely ceases to be a huge issue. I'd imagine that this world would end up looking a lot like ours by a hypothetical "2100 AD" tech level. They built on synthetic fuels and electricity because there was no alternative, and we'll have forcibly transitioned to them because we exhausted the fossil stopgap options.

deleted 4y ago

[deleted]

Roark66 4y ago

I find the idea that unless our civilisation changes its priorities from "unbounded growth" to "homeostasis" then we necessarily will suffer the "asymptotic burnout" comparable to papers written in 19th century predicting New York will drown in horse manure in next 75 years unless the growth is artificially stunted. Although the authors mention the role of periodic innovation as a factor that resets the curve of the resource consumption they dismiss it by stating the frequency of said innovation has to increase with increased energy usage and interconnectedness resulting in a certainty at some point innovation will not be fast enough to delay running out of resources. For this argument to work we have to accept unquestionably that "unbounded growth" has to continue until either a civilisation runs out of resources and regressed or achieves "enlightenment" and shifts its priorities towards homeostasis. To this I say why are they so sure, that as through growth of economic activity we raise our collective standard of living people don't start valuing their happiness over economic output? In fact observations of highly developed societies seem to support that. In addition the birth rate of people declines in modern societies often below replacement numbers so that "unbounded growth" looks really unlikely.

matthewdgreen 4y ago
We replaced horse manure as a waste product with greenhouse gases, which produced a local improvement but will very likely put large portions of New York City under water in this century. So based on the evidence accumulated so far, we haven’t demonstrated that we can find our way out of the resource/pollution dilemma. Maybe we will in the future!
- parkingrift 4y ago
  We already know how to find our way out. Stratospheric aerosol injection. We don’t need to invent anything new or spend significant sums of money. We will do it eventually, but only after green democrats finish their “perfect is the enemy of good” lifetime crusade.
  - AlexandrB 4y ago
    "Know" is doing a lot of work here. > Almost all work to date on stratospheric sulfate injection has been limited to modeling and laboratory work.[1] At best it seems like a good potential solution that need a lot more study. [1] https://en.m.wikipedia.org/wiki/Stratospheric_aerosol_injection https://en.m.wikipedia.org/wiki/Stratospheric_aerosol_inject...

omnicognate 4y ago

The Fermi "paradox" is such an annoying meme. We have no evidence that extraterrestrial life isn't absolutely everywhere. To think we do is to greatly misunderstand the scale of the galaxy.

MattPalmer1086 4y ago
Why do you find it annoying? Other than it isn't a paradox of course. It's not claiming that life doesn't exist, it just provides a framework to discuss the current absence of evidence for it. The "where are they" question. We have conducted a lot of surveys and found nothing. There was a recent survey of galaxies that looked for Kardashev level 3 civilisations (control over the energy output of a galaxy) and we see nothing. So it seems reasonable that they are no K3 civilisations out there in our light cone. Simple life might be common, but we can't currently look for that easily, although bio signatures of gases in atmospheres is increasingly possible. It's also possible that complex civilisations are out there, but we just haven't figured out what that would look like. It's an ongoing search. The one thing we do know is if it's out there, it's not obvious.
- omnicognate 4y ago
  I find it annoying because it's discussed on HN ad nauseam in debates that are speculative fiction at best and riddled with logical fallacies at worst. Take, for example, the "Chain of Reasoning" section of the Wikipedia page page about the "paradox", which ends with following two steps: > Since many of the stars similar to the Sun are billions of years older, Earth should have already been visited by extraterrestrial civilizations, or at least their probes. > However, there is no convincing evidence that this has happened. The "should" in the first doesn't follow from what goes before at all, and the second is one of the most basic logical fallacies: absence of evidence is not evidence of absence. And take your own point about "K3 civilisations". Let's lay it out: 1. A "K3 civilisation" is one that controls the energy output of a galaxy. 2. Therefore it would be detectable with our instruments. 3. Therefore the fact that we haven't detected one means there isn't one. This is just bad reasoning. 2 doesn't follow from 1 and 3 doesn't follow from 2. The "therefore" in 2 ignores the word "control" in "control of the energy output of a galaxy". It makes an implicit assumption that any civilisation in control of such resources would necessarily do something with those resources that would result in an amount of radiation detectable to our instruments being emitted in our particular direction, whether that's some focused signal directly targeted at us or some massive omnidirectional blast. Maybe they would choose to randomly set off supernova-sized blasts for shits and giggles, but maybe, you know, they wouldn't. For 2 to follow from 1 you need to know that such a civilisation would necessarily produce detectable signals and you don't. Then, for 3 to follow from 2 you have to assume that every signal reaching our planet that is capable of being detected by our instruments is in fact detected. That is hilariously far from being true. Yes, we have some amazing instruments, including ones that can capture enough light from a nearby planet to do spectroscopy on its atmosphere. But those instruments are not simultaneously pointed in every direction all the time. The exact number isn't knowable but certainly 99 and several 9s percent of the signals reaching the Earth at any one time that we could detect and analyse we are in fact not. You talk of surveys but the idea of "surveying" our galaxy (let alone the universe) sufficiently thoroughly to rule out the presence even of the sort of advanced civilisation that produces vast uncontrolled blasts of undirected energy (and of course there's no reason to think an advanced civilisation necessarily would) with current technologies and funding is laughable. You can't bootstrap knowledge from nothing. The universe is staggeringly vast and we've barely started to look at it. The knowledge we have at this stage places essentially no limits on the sorts of alien life that could exist or on how widespread it is. If you want to speculate about what's out there, please do. I love science fiction! Just don't pretend it's science and please don't claim certainty when your arguments achieve nothing of the sort.

BirAdam 4y ago

I think the Fermi Paradox is more easily explained by three things. 1. It is possible that self-aware life with the ability to manipulate the environment is rare. Most people assume that self-aware life will build cities, but crows, cetaceans, octopuses, and elephants don’t do so despite having quite a bit of smarts. They lack hands. 2. It is possible that the speed of light is a very real boundary and that cannot be broken limiting the ability of life to spread itself within a life time. As anything that persists spends energy to do so, it may be that living things won’t willingly take the chance for themselves and posterity of living on a ship for many generations. 3. Nuclear war. Most intelligent life is predatory. If you want to manipulate your environment, you also have to focus. Most animals with eyes on the front of their heads that can focus well, are also predators. That predatory instinct creates violence, and that leads to war in pack-oriented social predators. With enough advancement, nuclear weaponry and war may be the rule not the exception.

admax88qqq 4y ago
> living on a ship for many generations. Thanks to time dilation, with 1g of acceleration you can go anywhere in the galaxy and back in 40 years.
- elkos 4y ago
  provided faster than light travel is possible right? Cause the galaxy is pretty big isn't it?
  - 4gotunameagain 4y ago
    I think he means that your local time passed will be 40 years, while much longer for the rest of non accelerating people. And of course I have no idea if the maths check out :)
    - qayxc 4y ago
      > And of course I have no idea if the maths check out :) The galaxy is about 90,000 ly across so a time dilation of about 0.004 is required to get to the 40 yr figure. Doing the Lorentz transformation results in a required speed of 299,790 km/s or 99.999% the speed of light. Needless to say that this is indeed practically unachievable by any macroscopic space craft. Even if you were able to accelerate a ship to such speed, said ship wouldn't survive the journey as radiation from the blue-shifted light of stars in front of it as well as interstellar particles would destroy any known material.

stared 4y ago

My take (which does not involve maths, just analogy with other organisms) is that we are bacteria that eat all that's on a petri dish. Dying as a species is (IHMO) rather unlikely, except for external factors and a few contamination scenarios. Eating all resources, starving most population, and going back to a pre-industrial civilization. Except for a few living high-tech standards. But with devices, they can use but cannot replace.

bohadi 4y ago

The burnout-collapse trajectory is another kind of homeostasis, only one with very wide range of variation. Though that produces huge human suffering and lossy cultural transmission so it might be worth avoiding. But homeostatic awakening is continually underway, from 20th century discourse of technique and enframing to our modern drives for global sustainability. Would it not be wise to err on the side of caution, reaching for the stars at some slowest effective rate (Elons per millenium;) until we know more? Another concern is civilization may execute both futures parallelly via splitting: where some 'elite' Gosper glider-like sets off from home planet, and the Gosper glider gun remains to reset the cycle. If collapse assumed this is your K shaped recovery. The Fermi paradox does not overly worry me for some reason. Everything Is just so improbable really.

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AbrahamParangi 4y ago

There is an assumption embedded in the Fermi paradox which is that life might originate within an environment already colonized by life. This is not the case in our experience on earth. As far as we know, all life is related which means that all life descends from a common ancestor. If intelligent life relatively rapidly (say within 1M years) gains the ability to travel at near the speed of light and consume interstellar resources, then new life would never know. There is no case where you could look up and see a galactic empire because if you could see it then it would have been expanding long enough to reach you, and you wouldn’t exist.

LorenPechtel 4y ago
Disagree. Life on Earth showed up about as soon as it could. That says the development of life isn't a likely limit. We see only one form of life because having a head start let it outcompete everything else. We appear to be alone. That says something (or some combination of things) in the process of developing into a starfaring civilization must have billions-to-one odds against it. It's not planets--we see tons of planets. Earth-like ones don't show up much--but our detection techniques aren't very good at seeing Earth-like planets so we can't conclude much from that. The rapid appearance of life on Earth says that's not a likely barrier. Looking at history we have two candidates: the development of multi-cellular life and the development of intelligence. Both took billions of years on Earth. Note that humanity just squeaked in under the wire, about 99% of time Earth would be capable of evolving intelligence is already past. The sun has been slowly warming, this has driven more CO2 into limestone, offsetting the warming. This buffer has almost pegged, once it pegs solar warming turns into planetary warming and Earth is no longer suitable for species with long life cycles. If we are lucky we are extreme outliers in how fast one or both of those steps happened and the barrier is behind us. (This shouldn't be discarded on improbability--observer effect. Only a planet where that happened could develop a species that could note the issue.) If not, the limit is in the future. Either we destroy ourselves or we somehow turn inward and ignore the stars. Unfortunately, probably says it's one of the latter. It is possible for there to be a galactic empire and yet we exist--quarantine hypothesis. There's a galactic empire that strictly avoids any star systems with worlds where life can arise. However, such a galactic empire should be detectable anyway. A star wrapped in a dyson swarm will show a spectrum unlike anything we can see in the sky. From this we can conclude there are no dyson swarms in any part of the universe we can resolve stars. Earth shines in the radio spectrum. An ET pointing a radio telescope at us isn't going to be able to decode much of anything (any more than we could listen to a million voices at once) but they can see the energy.

csense 4y ago

This article claims population growth increases on shorter and shorter timescales, leading to infinite population growth. If this is true, we should have had baby boom, bigger echo boom, giant boom. Instead, we had baby boom, smaller echo boom, and now Social Security's about to implode because the original boomers are retiring without being replaced. (Or maybe being replaced by immigrants, which led directly to Donald Trump being elected and the near-implosion of our political system.) This article might be the basis for an interesting and thought-provoking sci-fi story. But if it's supposed to be a serious scientific prediction of what actual aliens in our own universe are like, it's just embarrassing. If you make claims of supposedly near-universal trends in alien societies and say those claims are basically guaranteed by math and physics, then your claims certainly ought to at least be consistent with what we observe in our one known data point of an actual intelligent civilization (ourselves). And for the claim of technological population acceleration, actual observation suggests the effect runs in the opposite direction, at least here on Earth.